JPH0225160A - Original reader - Google Patents

Abstract

PURPOSE:To suppress the vibration smaller and to avoid the use of useless power by arranging plural coolers in the subscanning direction and driving only a cooler at a required position. CONSTITUTION:Fan motors 100-1-100-4 being plural coolers are provided. At first the fan motor 100-1 is driven. A CCD unit 1 of a scanner section applies image reading of main scanning and a printer prints it out. The printing paper is moved in the subscanning direction by a prescribed quantity to prepare for the succeeding main scanning. The CCD unit 1 is moved in the subscanning direction toward a direction opposite to the direction of the home position by the prescribed quantity, when the next fan motor 100-2 is driven. The processing is repeated for plural number of times and the fan motors 100-3, 100-4 are being sequentially driven.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a document reading device, and particularly to a cooling device for one having a large document table.

(Prior Art) Conventionally, in devices for reading large size originals, fans and the like have been used to suppress the rise in temperature of the document table.
For example, when a cross flow fan or the like is used, one with a long axial length is used.

(Problems to be Solved by the Invention) However, as the length of the cross flow fan in the axial direction increases, vibration increases, which has a negative effect on high-precision image reading.

In particular, for devices that read large-sized originals such as Al size, a cooling bag δ equal to the length of the long side or short side of 594 x 840 am (Al size) is required.
The power consumption for cooling was large.

The present invention has been made to solve the problems of the prior art described above, and its objectives are to efficiently cool down the temperature rise during reading, reduce the influence of vibration, and further reduce power consumption. An object of the present invention is to provide a document reading device equipped with a cooling device that can reduce the amount of noise.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an apparatus for reading an image of a document, which includes a document table on which the document is placed, and a device that moves on the document table. An image of a predetermined width is read by one movement in the main scanning direction, and each time one main scanning is completed, the line is moved and sub-scanned in a stripe pattern, and the next main scanning is performed, resulting in scanning the entire surface. a reading unit, a plurality of cooling devices arranged in the sub-scanning direction to cool the document table and the reading unit, and a control means for sequentially driving the cooling devices located at a position where the reading unit is moving. and.

It is equipped with the following.

(Function) According to the present invention, a plurality of cooling devices obtained by dividing a conventional cooling device are arranged in the sub-scanning direction, and only the cooling device at a necessary position is driven.

Vibration can be suppressed to a minimum and there is no need to use unnecessary power.

(Embodiment) An embodiment of the present invention is shown in FIGS. 1 to 4, and FIG. 1 is a diagram for explaining a mechanical mechanism inside a scanner section of a document reading device. The CCD unit 1 which is the reading unit 1 is the CCD 2. This unit is composed of a lens 3, etc., and is moved on the rail 4 by a drive system in the main scanning direction consisting of a main scanning motor 5 fixed on the rail 4, a pulley 6, and a wire 8. When moving the CCD 2) 1 to the main scanning home position in the correction area 12 in the figure, the light shielding plate lO and the home fist position sensor (HP sensor) 11 are used to read the image in the main scanning direction. used for position control.

Both ends of the rail 4 rest on the other two rails 13 and 14, and are equipped with a sub-scanning motor 15, pulleys 16, 17, 18,
19, shafts 20 and 21, and wires 22 and 23, which are moved by a drive system in the sub-scanning direction. Light shielding plate 24, home
A position sensor (HP sensor) 25 is used for position control when moving the rail 4 as a home position for sub-scanning when reading a document such as a book or three-dimensional object placed on the document table glass 9.

FIG. 2 is an explanatory diagram of the reading operation. Correction of Figure 2-1
'The home position shown in JA12 (HP
Then, the CCD unit I is moved to a position where the CCD unit I is placed on the document platen glass 9, and the reading operation of the entire surface of the document placed on the document table glass 9 is started from there.

Prior to scanning the original, processing such as shading correction, black level correction, and color correction is performed in the correction area 12.
Thereafter, scanning in the main scanning direction is started by the main scanning motor 5 in the direction of the illustrated arrow. When the reading operation of the area indicated by
2. Perform movement in the sub-scanning direction. Then, as with the main scanning of the area (■), perform shading correction as necessary.
Performs processing such as black level correction and color correction, and performs a reading operation in the area (■).

By repeating the above scanning, the entire area from ■ to ■ is read, and after completing the reading of the area (■), COD 2) 1 is returned to the home fist position again. In this embodiment, Since the document platen glass 9 can read documents of the maximum Al size, in reality it must be scanned more times, but in this explanation, the operation is simplified to make it easier to understand.

Now, when reading one image, it is of course necessary to illuminate the original. A halogen lamp or the like is usually used for this lighting, but the halogen lamp generates a lot of heat when it is turned on. The halogen lamp is mounted on the CCD 2) 1 (not shown).
However, the effect of heat generation is not limited to CCD unit 1.
This will lead to an increase in the temperature of the document table glass 9, and if the temperature becomes too high, it is dangerous. Therefore, as shown in FIGS. 1 to 4, cooling by fan motors 100-1 to 100-4, which are a plurality of cooling devices, is required to accommodate the wide document table glass 9. However, since the COD unit 1 moves in the sub-scanning direction, it is not necessary for all the fan motors to rotate at the same time.On the contrary, when all the fan motors rotate at the same time, vibrations and
Noise is generated, which adversely affects image reading. Therefore, the fan motors 100-1 to 100-4 may be sequentially driven as the COD unit 1 moves.

Next, FIG. 3 is a perspective view of the document reading apparatus main body 31 having the scanner section shown in FIG. FIG. 4 is a schematic side view of FIG. 3, and in FIG.
4 is provided. Further, on the top surface of the apparatus, there are provided an original platen glass 9 for placing an original, and a pressing plate 32 for pressing the placed original. Also, inside the device there are a lens 3, a COD 2, etc. that constitute the COD unit 1.

Next, the operation of this embodiment will be described using the flowchart in FIG. There may be a fifth
The flowchart in the figure assumes that a printer is connected, and includes operations for feeding and discharging print paper. First, the start of the reading operation begins with the device main body 31 in FIG.
This is carried out by pressing a copy start key (not shown) in the operation unit 33 of. When this start key is pressed, the process first proceeds to step 5PIO, and the C
OD unit l is home.

Move to position. At the same time, in step 5r11, printing paper is fed to the printer, and in step 5P12, the first fan motor 100-1 is driven. Also, in step 5P13, the value of the internal counter of the CPU is cleared (N=0), -
The end of copying is determined for each main scan and branching is performed.

If copying is completed, the print paper is ejected from the printer in step SP21, and all fan motors are stopped in step 5P22 to end the copying operation.

If the copying is not completed, proceed to step 5P14, read the main scanning image with the COD unit 1 of the scanner section, and print it with the printer, step 5P.
In step 15, the printing paper is moved by a predetermined amount in the sub-scanning direction to prepare for the next main scanning. In step 5P16, the COD unit 1 is moved in the sub-scanning direction by a predetermined amount in the direction opposite to the home position. In step 5P17, C
The internal counter of the PU is incremented by 1 (in 7 increments) and it is determined whether N=2 in step 2 5P18. This means that when the COD unit moves after scanning twice as shown in Figure 2, the next fan motor (if the first fan motor is 100-1, then 100-2)
This is because it is configured to drive. That is, N=2
If so, change the drive order of the fan motors (for example, fan % -) in step 5P19.
00-1 Stops the fan motor Zoo-2 and drives the fan motor Zoo-2) (step 5r20), and at the same time sets the value N of the internal counter of the CPU to 0, and again counts the scans for two days. The loop process consisting of step 5P13 to step 5P20 is repeated multiple times, and the fan motor too-1-100-2-100-3→...
..., and are driven one by one in sequence. ) Finish one copy operation.

FIG. 6 is a circuit diagram of control means for implementing the present invention and executing the sequence according to the flowchart of FIG. 5. 601 is a buffer, and 602 is a drive transistor. 600 is a CPU, which generates signals for driving each fabric load. 50 is a main scanning motor;
60 is a sub-scanning motor, and 603 and 604 are a main-scanning motor driver and a sub-scanning motor driver, respectively.

(Other Embodiments) In the explanation so far, the position of the fan motor CCCD unit 18 to be driven among the plurality of fan motors is calculated by calculating the movement amount of the sub-scanning CCD unit 1 from the number of sub-scanning feeds using software. The position of the CCD unit l may be determined by providing a separate sensor to detect the position of the CCD unit l.

That is, in FIG. 7, 700-1, 700-2, and 700-3 are input to the CPU as an example.

Four sensors named 700-4 are provided. These sensors are provided at the positions shown in FIG. 2 and detect the position of the CCD unit 1, so that they can perform the same function as the sequence described above.

(Effects of the Invention) As explained above, according to the image reading device of the present invention, a plurality of small cooling devices are provided in the sub-scanning direction, and vibrations are suppressed by driving only the cooling devices at necessary positions. This has the effect of saving power.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an embodiment of the document reading device of the present invention, FIG. 2 is a plan view for explaining the operation sequence of FIG. 1, and FIG. 4 is a side view of the device shown in FIG. 3, FIG. 5 is a flow chart for operating the device shown in FIG. 1, and FIG. FIG. 7 is a circuit diagram of another embodiment. Explanation of symbols 31... Document reading device main body, 32... Press plate, 33... Operation unit. Figure 2 Figure 0O-7 KX, l-do IC)tF, 5 Figure Figure 7

Claims (1)

[Claims] A device for reading an image of a document, which includes a document table on which the document is placed, a device that moves on the document table, reads an image of a predetermined width by one movement in the main scanning direction, and performs one main scan. Each time the scanning is completed, the line is moved and sub-scanned in a striped pattern, and then the next main scan is performed, and as a result, the reading unit that scans the entire surface, and the document table and the reading unit are arranged in the sub-scanning direction in order to cool them. A document reading device comprising: a plurality of cooling devices; and a control means for sequentially driving the cooling devices at positions where the reading unit is moving.